Anomalous spring observations
We identified observations of plant phenophases in Nature’s Notebook (NN) that were earlier than normal in 2025. We compared 2025 observations with observations collected in 2009-2024 for plants within 100 km and within 1000 m elevation of the plant observed in 2025. We limited analyses to phenophases in 4 phenophase classes: initial vegetative growth (class 1), leaves or needles (3), flowers or cones (6), and open flowers or cones (7), and only evaluated whether an observation was early if there were at least 20 observations for that species and phenophase over 8 or more years between 2009 and 2024.
We classified a 2025 observation as early if it was earlier than 95% of first-of-year observations in 2009-2024, and as an outlier if it was a Tukey outlier (2025 observation earlier than Q1 - 1.5 * IQR). We also noted if the observation was as early or earlier than the earliest date ever recorded in NN for that species, phenophase, and region (earliest).
In the tables below, we list all of the 2025 observations that were considered early or an outlier by phenophase class. Histograms displaying distribution of observations in prior years that were used to assess 2025 potential anomalies are at the bottom of the document.
| Species | Functional type | ID | State | Lat | Lon | Elev (m) | Date | Early | Earliest | Outlier | No. Prior Obs. (Yrs) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Pacific poison oak | Deciduous broadleaf | 270778 | CA | 37.93 | -122.74 | 74 | 2025-01-18 | Yes | No | No | 57 (13) |
| common snowberry | Deciduous broadleaf | 253531 | OR | 44.94 | -123.02 | 50 | 2025-01-21 | Yes | Yes | Yes | 69 (13) |
| golden currant | Deciduous broadleaf | 150497 | NM | 35.10 | -106.68 | 1508 | 2025-01-20 | Yes | No | No | 33 (10) |
| northern spicebush | Deciduous broadleaf | 335285 | PA | 40.33 | -74.94 | 27 | 2025-01-17 | Yes | Yes | Yes | 28 (9) |
| northern spicebush | Deciduous broadleaf | 348399 | PA | 40.33 | -74.94 | 27 | 2025-02-19 | Yes | Yes | Yes | 28 (9) |
| northern spicebush | Deciduous broadleaf | 348400 | PA | 40.33 | -74.94 | 27 | 2025-02-19 | Yes | Yes | Yes | 28 (9) |
| pecan | Deciduous broadleaf | 246701 | OK | 34.77 | -96.66 | 315 | 2025-02-07 | Yes | No | Yes | 38 (8) |
| red alder | Deciduous broadleaf | 78535 | CA | 37.92 | -122.69 | 0 | 2025-01-16 | Yes | No | No | 37 (13) |
| sugar maple | Deciduous broadleaf | 205360 | NY | 43.01 | -78.78 | 168 | 2025-02-21 | Yes | No | No | 133 (9) |
| sweetgum | Deciduous broadleaf | 283106 | NC | 35.17 | -81.06 | 197 | 2025-02-04 | Yes | Yes | Yes | 27 (11) |
| sweetgum | Deciduous broadleaf | 336128 | NC | 35.28 | -81.09 | 226 | 2025-02-07 | Yes | Yes | Yes | 24 (10) |
| California live oak | Evergreen broadleaf | 87340 | CA | 37.36 | -122.13 | 97 | 2025-01-21 | Yes | No | No | 279 (14) |
| California live oak | Evergreen broadleaf | 28811 | CA | 37.93 | -122.74 | 75 | 2025-01-26 | Yes | No | No | 325 (14) |
| California live oak | Evergreen broadleaf | 87339 | CA | 37.36 | -122.13 | 97 | 2025-01-30 | Yes | No | No | 279 (14) |
| Species | Functional type | ID | State | Lat | Lon | Elev (m) | Date | Early | Earliest | Outlier | No. Prior Obs. (Yrs) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| American beech | Deciduous broadleaf | 335283 | PA | 40.33 | -74.94 | 27 | 2025-01-24 | Yes | Yes | Yes | 26 (9) |
| northern red oak | Deciduous broadleaf | 204864 | NY | 43.01 | -78.78 | 168 | 2025-02-13 | Yes | Yes | Yes | 39 (10) |
| northern red oak | Deciduous broadleaf | 204866 | NY | 43.01 | -78.78 | 168 | 2025-02-13 | Yes | Yes | Yes | 39 (10) |
| northern red oak | Deciduous broadleaf | 204863 | NY | 43.01 | -78.78 | 168 | 2025-02-17 | Yes | No | No | 39 (10) |
| northern red oak | Deciduous broadleaf | 204858 | NY | 43.01 | -78.78 | 168 | 2025-02-18 | Yes | No | No | 39 (10) |
| red maple | Deciduous broadleaf | 204873 | NY | 43.01 | -78.78 | 168 | 2025-02-18 | Yes | No | No | 63 (8) |
| red maple | Deciduous broadleaf | 204875 | NY | 43.01 | -78.78 | 168 | 2025-02-18 | Yes | No | No | 63 (8) |
| red maple | Deciduous broadleaf | 199342 | NY | 43.01 | -78.78 | 168 | 2025-02-21 | Yes | No | No | 63 (8) |
| red maple | Deciduous broadleaf | 204872 | NY | 43.01 | -78.78 | 168 | 2025-02-21 | Yes | No | No | 63 (8) |
| sugar maple | Deciduous broadleaf | 297758 | MA | 42.37 | -71.15 | 12 | 2025-02-03 | Yes | Yes | Yes | 233 (16) |
| sugar maple | Deciduous broadleaf | 205362 | NY | 43.01 | -78.78 | 168 | 2025-02-14 | Yes | Yes | Yes | 144 (8) |
| sugar maple | Deciduous broadleaf | 205366 | NY | 43.01 | -78.78 | 168 | 2025-02-19 | Yes | No | Yes | 144 (8) |
| sweetgum | Deciduous broadleaf | 336128 | NC | 35.28 | -81.09 | 226 | 2025-02-07 | Yes | Yes | Yes | 23 (8) |
| Eastern Mojave buckwheat | Drought deciduous broadleaf | 31968 | CA | 34.68 | -120.04 | 357 | 2025-01-10 | Yes | Yes | Yes | 28 (10) |
| blue paloverde | Drought deciduous broadleaf | 50745 | AZ | 32.25 | -110.91 | 746 | 2025-01-12 | Yes | No | No | 78 (11) |
| blue paloverde | Drought deciduous broadleaf | 257146 | AZ | 32.40 | -110.98 | 767 | 2025-01-21 | Yes | No | No | 78 (11) |
| catclaw acacia | Drought deciduous broadleaf | 237801 | AZ | 32.40 | -111.00 | 801 | 2025-01-10 | Yes | Yes | Yes | 24 (9) |
| desert willow | Drought deciduous broadleaf | 50750 | AZ | 32.25 | -110.91 | 746 | 2025-01-12 | Yes | No | Yes | 88 (12) |
| desert zinnia | Drought deciduous broadleaf | 278921 | AZ | 32.40 | -111.00 | 801 | 2025-01-10 | Yes | No | No | 46 (8) |
| honey mesquite | Drought deciduous broadleaf | 11431 | CA | 34.13 | -116.04 | 602 | 2025-02-03 | Yes | No | Yes | 24 (12) |
| ocotillo | Drought deciduous broadleaf | 139414 | AZ | 32.25 | -110.91 | 746 | 2025-01-26 | Yes | No | No | 142 (15) |
| velvet mesquite | Drought deciduous broadleaf | 257140 | AZ | 32.40 | -110.98 | 767 | 2025-01-21 | Yes | No | No | 104 (13) |
| black grama | Graminoid | 343755 | NM | 32.59 | -106.84 | 1330 | 2025-01-15 | Yes | No | No | 199 (8) |
| black grama | Graminoid | 343756 | NM | 32.59 | -106.84 | 1330 | 2025-01-15 | Yes | No | No | 199 (8) |
| black grama | Graminoid | 343768 | NM | 32.59 | -106.84 | 1330 | 2025-01-15 | Yes | No | No | 199 (8) |
| Species | Functional type | ID | State | Lat | Lon | Elev (m) | Date | Early | Earliest | Outlier | No. Prior Obs. (Yrs) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| buck-horn cholla | Cactus | 117070 | AZ | 33.60 | -111.81 | 533 | 2025-02-06 | Yes | No | No | 79 (9) |
| Siberian elm | Deciduous broadleaf | 63893 | NM | 35.10 | -106.68 | 1508 | 2025-01-20 | Yes | No | No | 54 (11) |
| arroyo willow | Deciduous broadleaf | 29433 | CA | 37.92 | -122.69 | 0 | 2025-01-16 | Yes | Yes | Yes | 43 (13) |
| arroyo willow | Deciduous broadleaf | 275211 | CA | 38.05 | -122.87 | 25 | 2025-01-17 | Yes | Yes | Yes | 43 (13) |
| black elderberry | Deciduous broadleaf | 4194 | CA | 34.46 | -119.71 | 229 | 2025-01-22 | Yes | No | No | 289 (13) |
| eastern redbud | Deciduous broadleaf | 347346 | MD | 39.03 | -77.02 | 109 | 2025-01-30 | Yes | Yes | Yes | 66 (8) |
| flowering dogwood | Deciduous broadleaf | 210868 | NC | 35.83 | -82.55 | 693 | 2025-02-13 | Yes | No | No | 153 (12) |
| red maple | Deciduous broadleaf | 210872 | NC | 35.83 | -82.55 | 693 | 2025-01-28 | Yes | No | Yes | 227 (14) |
| red maple | Deciduous broadleaf | 335280 | PA | 40.33 | -74.94 | 27 | 2025-02-01 | Yes | Yes | Yes | 24 (9) |
| red maple | Deciduous broadleaf | 326716 | PA | 39.81 | -76.35 | 154 | 2025-02-03 | Yes | Yes | Yes | 50 (8) |
| star magnolia | Deciduous broadleaf | 79974 | CA | 38.38 | -122.51 | 109 | 2025-02-06 | Yes | No | No | 25 (8) |
| sugar maple | Deciduous broadleaf | 210871 | NC | 35.83 | -82.55 | 693 | 2025-02-10 | Yes | Yes | Yes | 33 (9) |
| sweetgum | Deciduous broadleaf | 153521 | LA | 30.05 | -89.88 | 0 | 2025-01-07 | Yes | No | No | 28 (8) |
| bald cypress | Deciduous conifer | 127552 | LA | 30.05 | -89.88 | 0 | 2025-01-15 | Yes | No | No | 37 (8) |
| brittlebush | Drought deciduous broadleaf | 199265 | AZ | 32.34 | -110.98 | 764 | 2025-01-14 | Yes | Yes | Yes | 65 (9) |
| ocotillo | Drought deciduous broadleaf | 321434 | AZ | 33.60 | -111.81 | 533 | 2025-01-31 | Yes | No | No | 39 (10) |
| California live oak | Evergreen broadleaf | 28811 | CA | 37.93 | -122.74 | 75 | 2025-01-19 | Yes | No | Yes | 190 (13) |
| California live oak | Evergreen broadleaf | 87340 | CA | 37.36 | -122.13 | 97 | 2025-01-21 | Yes | No | No | 147 (13) |
| California live oak | Evergreen broadleaf | 87339 | CA | 37.36 | -122.13 | 97 | 2025-01-30 | Yes | No | No | 147 (13) |
| coyotebrush | Evergreen broadleaf | 18492 | CA | 37.98 | -122.13 | 63 | 2025-01-06 | Yes | Yes | Yes | 364 (14) |
| creosote bush | Evergreen broadleaf | 246469 | AZ | 32.37 | -110.97 | 800 | 2025-01-05 | Yes | Yes | Yes | 209 (13) |
| creosote bush | Evergreen broadleaf | 102258 | AZ | 32.24 | -110.91 | 755 | 2025-01-10 | Yes | Yes | Yes | 207 (13) |
| creosote bush | Evergreen broadleaf | 50751 | AZ | 32.25 | -110.91 | 746 | 2025-01-12 | Yes | No | No | 207 (13) |
| creosote bush | Evergreen broadleaf | 199258 | AZ | 32.34 | -110.98 | 764 | 2025-01-14 | Yes | No | No | 209 (13) |
| creosote bush | Evergreen broadleaf | 257149 | AZ | 32.40 | -110.98 | 767 | 2025-01-19 | Yes | No | No | 209 (13) |
| jojoba | Evergreen broadleaf | 50747 | AZ | 32.25 | -110.91 | 746 | 2025-01-09 | Yes | Yes | Yes | 90 (13) |
| jojoba | Evergreen broadleaf | 50746 | AZ | 32.25 | -110.91 | 746 | 2025-01-12 | Yes | No | No | 90 (13) |
| olive | Evergreen broadleaf | 347073 | CA | 37.57 | -122.03 | 12 | 2025-01-16 | Yes | Yes | Yes | 29 (10) |
| redbay | Evergreen broadleaf | 151042 | MS | 30.50 | -89.67 | 18 | 2025-01-30 | Yes | No | No | 68 (8) |
| redbay | Evergreen broadleaf | 151043 | MS | 30.50 | -89.67 | 18 | 2025-01-30 | Yes | No | No | 68 (8) |
| redbay | Evergreen broadleaf | 250659 | MS | 30.40 | -88.65 | 0 | 2025-02-05 | Yes | No | No | 86 (8) |
| wax myrtle | Evergreen broadleaf | 283389 | LA | 30.32 | -89.94 | 3 | 2025-01-12 | Yes | No | No | 56 (8) |
| wax myrtle | Evergreen broadleaf | 283390 | LA | 30.32 | -89.94 | 3 | 2025-01-12 | Yes | No | No | 56 (8) |
| Douglas-fir | Evergreen conifer | 28798 | CA | 37.93 | -122.74 | 74 | 2025-01-18 | Yes | No | No | 31 (13) |
| eastern redcedar | Evergreen conifer | 84087 | NY | 41.75 | -74.12 | 89 | 2025-01-29 | Yes | Yes | Yes | 38 (11) |
| blue oak | Semi-evergreen broadleaf | 87379 | CA | 37.36 | -122.13 | 112 | 2025-01-28 | Yes | Yes | Yes | 36 (12) |
| blue oak | Semi-evergreen broadleaf | 53668 | CA | 37.36 | -122.13 | 112 | 2025-01-30 | Yes | Yes | Yes | 36 (12) |
| Species | Functional type | ID | State | Lat | Lon | Elev (m) | Date | Early | Earliest | Outlier | No. Prior Obs. (Yrs) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| star magnolia | Deciduous broadleaf | 79974 | CA | 38.38 | -122.51 | 109 | 2025-02-06 | Yes | No | No | 27 (9) |
| brittlebush | Drought deciduous broadleaf | 246477 | AZ | 32.37 | -110.97 | 800 | 2025-02-15 | Yes | No | No | 67 (10) |
| California live oak | Evergreen broadleaf | 270774 | CA | 37.93 | -122.74 | 75 | 2025-01-12 | Yes | Yes | Yes | 141 (13) |
| California live oak | Evergreen broadleaf | 87339 | CA | 37.36 | -122.13 | 97 | 2025-01-21 | Yes | No | No | 107 (13) |
| coyotebrush | Evergreen broadleaf | 18492 | CA | 37.98 | -122.13 | 63 | 2025-01-06 | Yes | Yes | Yes | 334 (14) |
| creosote bush | Evergreen broadleaf | 102258 | AZ | 32.24 | -110.91 | 755 | 2025-01-10 | Yes | Yes | Yes | 368 (16) |
| creosote bush | Evergreen broadleaf | 50751 | AZ | 32.25 | -110.91 | 746 | 2025-01-12 | Yes | No | Yes | 368 (16) |
| creosote bush | Evergreen broadleaf | 199258 | AZ | 32.34 | -110.98 | 764 | 2025-01-14 | Yes | No | Yes | 369 (16) |
| jojoba | Evergreen broadleaf | 199269 | AZ | 32.34 | -110.98 | 764 | 2025-01-14 | Yes | Yes | Yes | 86 (13) |
| olive | Evergreen broadleaf | 347073 | CA | 37.57 | -122.03 | 12 | 2025-01-16 | Yes | Yes | Yes | 20 (8) |
| Douglas-fir | Evergreen conifer | 28798 | CA | 37.93 | -122.74 | 74 | 2025-01-18 | Yes | No | No | 24 (11) |